1. Technical Field
The present disclosure relates to an optical pickup and an optical read/write apparatus comprising the optical pickup.
2. Description of the Related Art
A known read/write apparatus that reads and writes data from/on an optical storage medium such as a write-once or rewritable optical disc reads data that has been just written and compares the data that has been read to the data to write in order to detect an error, if any, lest the write operation should fail due to a defect on the storage medium. That is to say, by alternately writing data and checking the data just written time-sequentially over and over again, a verify operation gets done.
According to such a method, however, it is difficult to increase the write speed sufficiently. Also, even though this method is applicable effectively to an optical disc or any other medium with good random accessibility, it is hard to use such a method in a medium with poor random accessibility such as an optical tape with a great tape length, which does not allow the user to change the tape running direction or return to the same tape position easily.
Thus, to meet such a demand, a so-called “DRAW (direct read after write)” technique for performing a write operation and a read operation for verification purposes at the same time has been proposed in Japanese Laid-Open Patent Publications No. 63-249941 and No. 2005-038536.